lang="EN-US">The Detroit area emerged as a significant metropolitan
region within the United States as construction of a regional freeway system
was completed in the 1950s and 1960s. With these commuting ties allowing social
and economic integration across a larger area, the
Detroit name sometimes refers to the three-county Urban Area
(population 3,734,090, area of 1,337 square miles (3,460 km), as of the
2010 United States Census), the six-county Metropolitan Statistical Area (2010
Census population of 4,296,250, area of 3,913 square miles (10,130 km)),
or the nine-county Combined Statistical Area (2010 Census population of
5,218,852, area of 5,814 square miles (15,060 km)). The Detroit–Windsor
area, a commercial link straddling the Canada–U.S. border, has a total
population of about 5,700,000. The Detroit metropolitan region currently holds
roughly one-half of the state's population.
Known as the world's traditional automotive center,
"Detroit" is a metonym for the American automobile industry and an
important source of popular music legacies celebrated by the city's two
familiar nicknames, the Motor City
and Motown. Other nicknames
arose in the 20th century, including City
of Champions beginning in the 1930s for its successes in individual and
team sport, The D, Hockey town (a trademark owned by the
city's NHL club, the Red Wings), Rock
City (after the Kiss song "Detroit Rock City"), and The 313 (its telephone area code).
Detroit's auto industry was an important element of the American "Arsenal
of Democracy"